Shank-stiffening device



July 14, 1925. I 1,545,554

K. ENGEL SHANK STIFFENING DEVICE Original Filed Feb. 4, 1918 M 4 i lF1514 7 7 5 v l 1 2 V//// ////////////////7 v//l; III, II, 8

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Patented July 14, 1925..

UNITED STATEVSPATENT OFFICE.

KARL ENGEL, OF ARLINGTON, MASSACHUSETTS, ASSIGNQR TO UNITED SHOE MA-CHINERY CORPORATION, 01? IE'ATERSON, NEW JERSEY, .A CORPORATION OF NEWJERSEY.

SHANK-STIFFENING DEVICE.

Original application filed February 4, 1918, Serial No. 215,339. Dividedand this application filed July 9,

1920. Serial No- 395,054.

T 0 all whom it may concern:

Be it known that I, KARL ENGEL, a citizen of the United States, residingat Arlington, in the county of Middlesex and State of Massachusetts,have invented certain Improvements in Shank-Stiffening Devices, of whichthe following description, in connection with the accompanying drawings,is a specification, like reference characters on the drawings indicatinglike parts in the several figures.

This invention relates to devices for boots and shoes.

The invention is herein set forth with shank stiffening specialreference to molded metal shank stiffeners arranged to be attached, asby prongs struck up from the body thereof, to

a sole member or other suitable portion of a shoe and particularly,though by no means, necessarily, in accordance with the method describedand claimed in my application Serial No. 215,339, filed February 4, 1918and resulting in Patent No 1,281,540,

granted October 15, 1918, and referred to in my copending applicationSerial No. 257,- 954, filed October 14, 1918 and resulting in Patent No.1,464,501, granted August 14, 1923, of both of which this application isa division.

According to the method of preparing outs'oles disclosed in the patentabove identified, a shank stiffening device of such longitudinal andtransverse conformation as is suitable to the shoes under considerationis associated with a sole member as an incident to the moldingof thesole member to the desired shape. It is essential that the shankstiffening device become finally associated with the sole member in amanner to retain the solev member in the shape to which it is molded andthat the shank stiffener be of such conformation and material as toprovide the required rigidity and support for the longitudinally archedshank portion of the shoe. 'A further desirable property of the shankstiffener is that it be capable of final attachment'to the sole memberof the shoe during the molding of the sole, or otherwise, withoutimpairing or marring the finished appearance of the sole member or ofthe shoe.

lVith these requirements in mind the shank ifi i r 9 the Present inventn mof approximately prises a metal plate molded to present longitudinaland transverse curvatures and provided at or near its ends withattaching means such as prongs bent up at an angle from the body portionto be embedded in the substance of a sole member to attach the shankstiffener thereto. The illustrated shank stiffener is provided with apair of attaching prongs bent up from the forward portion of the shankstiffener at an angle and with attaching prongs at the rear bent upapproximately at right angles to the body of the shank stiffener, thelatter acting effectively as impaling prongs to prevent endwise movementof the stiffening device after it is on the sole. By reason of theangular disposition of the prongs on the forward end of the shankstiffener'the prongs are enabled readily to enter the substance of thesole member if the stiffener and sole member are molded together. On theother hand, if the sole member is molded prior to the attachment of theshank stiffener thereto, the inclination of the prongs at the forwardend of thestiffener is in no way disadvantageous. The prongs at the rearend of the device are effective to prevent relative longitudinalmovement of the two parts under any circumstances This plurality ofprongs at or near each end of the device assists materially inmaintaining the transverse curva-" ture of the sole and renders thedevice substantially more effective than it would be if a (single prongwere relied upon at either en Other objects and features of theinvention, including novel locating means comprising a locating or jighole to determine the longitudinal position of the stiffener and aslotto determine its angular and therefore its lateral position, will appearfrom the following description when considered in connection with theaccompanying drawings which embodiment of the'invention and theinvention will then be defined inthe appended claims. i I

Fig. '1 is a perspective view of a shank stiffener made in accordancewith the invention;

Fig. 2 illustrates a side elevation and Fig. 3 a v e o a b anks 1 9 a nkillustrate a preferred stifiener, in accordance with a preferredembodiment of the invention, may be formed;

Fig. 4- is a view partly in longitudinal cross-section showing the shankstiffener assembled with the shaping molds for the op.- eration ofshaping the said element;

Fig. 5 illustrates in longitudinal section the operation of the shapingmolds;

Fig. 6 is a longitudinal cross section illustrating a shoe sole and theshank stillener of the present invention assembled lolthe operation ofthe sole-shaping molds; and

Fig. 7 is a detail section showing an attaching prong provided at theforward end of the shankstillener.

In the drawings, 1 represents a blank from which the shank stilfener maybe formed. This blank is out out from sheet metal possessing the rightdegree of hardness to meet the requirements of the kind of shoe to bemade and to st-ilfen the shank portion of the quality of sole to be usedPreferably, and as herein show-n, the blank is shaped generally }to litwithin the'inseam of the shoe {from the heel seat portion tosubstantially the break or ball line or the shoe.

4 In cutting out, this blank a projecting prong 21s formed at each ofthe forward corners and.

rear corners of the blank and two holes 16 and 18 are also 'formed inthe blankas shown in Figs. 1 and The hole 16 is located substantiallycentrally of {the blank at the point of the highest longitudinalcurvature ofthe linally shaped shank stiilencr while the hole 18 whichis elongated is located forwardly of the. hole 16 and in the median lineof the blank. "These holes have no utility in the shank stifiener per sebut serve the purpose of f-acilitating'the manufacture of the shank. Toenable'ihe. prongs 2 at the forward end of the blank readily to enterthe sole in predetermined direction they are preferably. beveled asshownin Fig. 7. The

' blank as thus out out is molded to the precise shape that it isdesired that the shank portion of the both as to longitudinal curvatureora'roh and as to transverse curvature. Also the molding-operationserves to bend the prongs 2 into the desiredangu lar relation to the'iody of the blank.

Conveniently the molding of the shank stiffener blank may be donebetween co-opcrating dies or molds 4 and '6 which may be of anywell-known construction and operated by anysuitable mechanism. Thebottom mold 6 is shaped to present the longitransversely curved surfacepositioning pins or pilots 5 are fixed in the 18in the blank 1 and holdit in position in the mold the pin 5 projec'tingthrough sole of the shoeshall possess,

mold so as to project through the holes 16,

the hole 16 preventing the blank from moving endw'ise on the moldingsurface .and the elongated slot 18 preventing lateral displacement ofthe shank member on the mold when pressure is applied, but allowing theblank to be curved "longitudinally. At either corner of the moldingsurface prong-shaping recesses 7 are provided to receive and properlyshape the projecting prongs 2 of the blank. The too-operating mold 4presents a longitudinally and transversely curved molding surface whichis complemental to that of the mold 6 and is provided with recesses "Sto receive the projecting ends of the blank-positioning pilots 5.Depending from the molding surface of the mold at each corner s a prongbending member 9' Fig. 1. This shape preserving element has alongitudinal and transverse curvature corresponding to thelongitudinally arched conformation of the shank of the shoe and atransverse curvature corresponding to the lateral convexity desired forthe shank portion of the sole. This transverse curvature of thestiffening device is of considerable practical importance inasmuch as itserves to increase the rigidity and strength of the shank, so muchso infact, that under ordinary conditions relatively thin piece of metal maybe used to constitute the stiffener. Moreover, it will ordinarily befound unnecessary to-temiper :the metal after the desired shape has beenimparted to it in order lion-it to have the required strength andstiffness.

The sh ank stiffener, as a result of the shaping operations, conforms tothe molding face of the molds which are to mold a sole member fora shoein the desired manner. Inthe use of the shank stiffener in accordancewith the method disclosed in the aboveddcntified patents andapplications, the stiffener device 1 is placed upon the bottom mold 12.The relative positioning of the shank stiffener on this mold isconveniently aide'd by means of pilots 15 fixed in the mold 1'2.Thereafter, a sole member 10 which has been previously died outsubstantially to edge contour the sole molds in proper longitudinal andtransverseposition all as indicated in Fig. 6. 'These molds 12 and 14.are operated by mean's well-kno'wn in the moldingart and in the first Ihajse oft' he molding operation the sole member is conformedlongitudinally and transversely into near parallelism with the opposedface of the stilie'n'ing device 1 is assembled in immaterial whetherthey and the molding surfaces of themolds 12, 14. As an incident to thisphase of the molding operation the sole member is forced upon the prongs2 at the forward end of the stiffener which by reason of theirinclination act to draw the sole member rearwardly in the mold and intofinally attached position on the stiffener. As the pressure continuesthere being, of course, no separate stages in the application of themolding pressure, the prongs 2 at the rear of the stiffener are forcedinto the sole memben and owing to their inclination relatively to theforward prongs 2 act to impale the stiffener on the sole and preventendwise movement of the stiffener which would tend to withdraw theforward prongs from the sole member. In the final application ofpressure the sole member is molded to the exact shape which has beenpreviously given to the shank-stiffening device and inasmuch as thestiffener becomes finally affixed to the sole member by reason of theprongs as an incident to the molding operation the stiffener is thusenabled effectively to maintain the conformation imparted to the solemember. This latter function of the stiffener is assisted to a largeextent by the provision of the prongs at either of the forward cornersof the stiffener since they engage the sole at either side and thus areeffective in holding the sole member to the transverse convexityimparted to it. It will be noted that the inclination of the prongs atthe forward end of the stiffener enables them finally to enter the solewithout injuring or marring the outer tread surface of the sole. Sincethe rear prongs are located within the area of the heel seat it isproject through to the tread side of the sole.

The bulkiness of the shoe in the shank need not be increased by thepresence of the stiffening element to any appreciable extent inasmuch assufficient pressure may be applied during the sole molding operation toembed the stiffening device in the sole, this being possible because itsconstruction is such that maximum strength and rigidity are obtained inthe stiffener with a mini-' mum thickness of the metal plate.

Having thus described my invention, what I claim as new and desire tosecure by Letters Patent of the United States is:

1. As an article of manufacture, a shank stiffener molded to thelongitudinal and transverse curvature of a shoe shank and having at itsfront end an attaching prong bent up from the body portion at an angleof about to stand in a direction for the sole to be drawn on to theprong during the longitudinal melding of a superposed sole and providedat its rear end with a prong bent up at an angle of about 90 to impalethe superposed sole.

2. As an article of manufacture, a shank stiffener molded to thelongitudinal curva-' ture of a shoe shank and having at its front endanattaching prong bent up from the body portionatan angle of about 60 tostand in a direction for the sole to be drawn onto the prong during-thelongitudinal molding of a superposed sole and provided at its rear endwith a prong bent up at an angle of about 90 to impale the superposedsole, and provided intermediate its ends with means to co-operate with asole mold for holding the shank stiffener against longitudinaldisplacement during the sole molding operation.

3. As an article of manufacture, a shank stiffener blank having means atopposite ends to secure it to a shoe sole, and provided with a circularhole closely to embrace a locating pin in a shank stiffener mold duringthe manufacture of a stiffener from the blank and a similar locating pinin a sole mold when a sole and the stiffener are being operated upon tomold the sole, to prevent longitudinal movement in either direction ofthe blank and stiffener in the respective molds, and further providedwith an elongated slot closely to embrace opposite sides of a secondlocating pin in each mold, to determine the angular position of theblank in the first mold while allowing the material of the blank to movelongitudinally past the second pin as the blank is molded and todetermine the angular position of the stiffener in the second mold, thehole and slot operating to predetermine exactly the position of theblank of the stiffener in the second mold.

4. As an article of manufacture, a shank stiffener provided with spacedlocating holes, one being circular closely to embrace a locating pin ina sole mold to prevent longitudinal movement of the stiffener therein,and the other being elongated lengthwise of the stiffener and adapted toengage opposite sides of a second locating pin to determine the angularposition with respect to the first locating pin, said stiffener beingfurther provided with means for attaching it to a sole.

5. As an article of manufacture, a shank stiffener molded to thelongitudinal curvature of the shank portion of the shoe in which it isto be incorporated and transversely arched to increase its rigidity, thestiffener being formed with an edge at the front end thereof extendingsubstantially at right angles to the length of the stiffener and havingan attaching prong bent up from the body portion at each extremity ofsaid edge and substantially along the line of said edge, and a pair ofattaching prongs bent up from the opposite end of the body portion.

6. As an article of manufacture, a shank in the first mold and 5 havinga pa stifiener molded to the l'dngibuclinal curvafare of the shankportion of the shcej which it igbo ineeitponated and Ltraiasverselyarched to increase its rigidity, and of attaching prongs farmed frommaterial located without theouflineof the shank stiifener aheaehextremity :thenedian line of the s-ti-ffenep In testimony whereof I havesigned my name t0 :this specification.

KARL EN GEL.

